Re: Compile time executed functions

[Stephen Leake <stephen.a.leake.1@gsfc.nasa.gov>]

Jean-Marc Bourguet <jbourguet@free.fr> writes:

> > : First feature, things like
> > :    enum { foo = x+y*z; }
> > : are valid as long as x, y and z value are known at compile time and have
> > : to be evaluated at compile time.
> > 
> > Isn't this usually resolvable as a constant by most Ada compilers? At least
> > the ones I know will usually do so.
> 
> It is quite difficult to come with the equivalent in Ada.  One is
>    foo : constant = x+y*z;
> is indeed resolvable by most Ada compiler.

Actually, since C and C++ define an enum to be just a named int, this
is the _exact_ equivalent in Ada.

Perhaps you meant to say that 

package A_Package is

   X : constant := 2;
   Y : constant := 3;
   Z : constant := 4;

   type Bar is (Foo);
   for Bar use (Foo => x + y * z);

end A_Package;

is not legal Ada. However, GNAT 3.14a disagrees with you.

-- 
-- Stephe